Go to: http://www.kmkt.ro/search/index.php?toSearch="arany+lacinak"&yearStart=&yearEnd=&language=# click on the last hit's Details link. In the right area's iframe the scrollbar cannot be scrolled with the mouse, scrollwheel works though.
Corrected link: http://www.kmkt.ro/search/main/index.php?toSearch="arany+lacinak"&yearStart=&yearEnd=&language=#
In trunk with 4.5 it is even worse, the vertical scrollbar appears only after clicking in the iframe.
behaviour on 4.2.90/4.2.91 whith qt 4.5.1: the scrollbar is there but not drawn when the page uses javascript to load the iframe. it get's drawn as soon as the iframe get's the focus or move the mouse where the scrollbar should be. i stripped down the page to a simple testcase
Created attachment 34670 [details] save as index.html
Created attachment 34671 [details] save as iframe.html (testcase)
Seems to work fine in 4.7.1